hdu 4694 Important Sisters【支配树】

求出支配树输出到father的和即可

支配树见：https://blog.csdn.net/a710128/article/details/49913553

#include<iostream>
#include<cstdio>
#include<vector>
#include<cstring>
using namespace std;
const int N=300005;
int n,m,h[N],cnt,se[N],id[N],rl[N],fa[N],dfn[N],tot,f[N],v[N];
long long ans[N];
vector<int>p[N],d[N];
struct qwe
{
	int ne,to;
}e[N];
int read()
{
	int r=0,f=1;
	char p=getchar();
	while(p>'9'||p<'0')
	{
		if(p=='-')
			f=-1;
		p=getchar();
	}
	while(p>='0'&&p<='9')
	{
		r=r*10+p-48;
		p=getchar();
	}
	return r*f;
}
void add(int u,int v)
{
	cnt++;
	e[cnt].ne=h[u];
	e[cnt].to=v;
	h[u]=cnt;
}
void dfs(int u)
{
	dfn[u]=++tot;
	rl[tot]=u;
	for(int i=h[u];i;i=e[i].ne)
	{
		p[e[i].to].push_back(u);
		if(!dfn[e[i].to])
		{
			fa[e[i].to]=u;
			dfs(e[i].to);
		}
	}
}
int zhao(int x)
{
	if(f[x]==x)
		return x;
	int fa=zhao(f[x]);
	if(dfn[se[v[f[x]]]]<dfn[se[v[x]]])
		v[x]=v[f[x]];
	return f[x]=fa;
}
int main()
{
	while(~scanf("%d%d",&n,&m))
	{
		memset(h,0,sizeof(h));
		memset(id,0,sizeof(id));
		memset(dfn,0,sizeof(dfn));
		memset(ans,0,sizeof(ans));
		cnt=0;tot=0;
		for(int i=1;i<=n;i++)
			p[i].clear(),d[i].clear(),f[i]=v[i]=se[i]=i;
		for(int i=1;i<=m;i++)
		{
			int x=read(),y=read();
			add(x,y);
		}
		dfs(n);
		for(int i=tot;i>=2;i--)
		{
			for(int j=0;j<p[rl[i]].size();j++)
			{
				if(dfn[p[rl[i]][j]]<dfn[rl[i]])
					se[rl[i]]=(dfn[se[rl[i]]]<dfn[p[rl[i]][j]])?se[rl[i]]:p[rl[i]][j];
				else
				{
					zhao(p[rl[i]][j]);
					se[rl[i]]=(dfn[se[rl[i]]]<dfn[se[v[p[rl[i]][j]]]])?se[rl[i]]:se[v[p[rl[i]][j]]];
				}
			}
			f[rl[i]]=fa[rl[i]];
			d[se[rl[i]]].push_back(rl[i]);
			for(int j=0;j<d[fa[rl[i]]].size();j++)
			{
				zhao(d[fa[rl[i]]][j]);
				id[d[fa[rl[i]]][j]]=(dfn[se[v[d[fa[rl[i]]][j]]]]<dfn[se[d[fa[rl[i]]][j]]])?v[d[fa[rl[i]]][j]]:fa[rl[i]];
			}
		}
		for(int i=2;i<=tot;i++)
			if(id[rl[i]]!=se[rl[i]])
				id[rl[i]]=id[id[rl[i]]];
		for(int i=1;i<=n;i++)
			ans[i]=0;
		for(int i=1;i<=tot;i++)
		{
			ans[rl[i]]+=rl[i];
			if(id[rl[i]])
				ans[rl[i]]+=ans[id[rl[i]]];
		}
		for(int i=1;i<n;i++)
			printf("%lld ",ans[i]);
		printf("%lld\n",ans[n]);
	}
	return 0;
}